Regulator with segmented body

ABSTRACT

The regulator connects to a high pressure fluid supply and regulates the pressure to a downstream apparatus. If an over-pressure occurs, it is vented to atmosphere. A segmented body reduces production costs. An elongate control stem engages a supply seal assembly and a vent seal assembly and moves axially with respect to these seal assemblies to achieve regulation and venting. Both the supply seal assembly and the vent seal assembly are bi-directional and operate when forces are applied from opposing directions.

CROSS REFERENCED TO RELATED APPLICATION

This is a continuation-in-part of U.S. patent application Ser. No09/640,401 filed on Aug. 16, 2000 for a Precision Regulator, whichapplication is now pending.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention is a regulator used for controlling fluidpressures in a downstream apparatus. The regulator can also vent excessdownstream pressures to atmosphere. The body is segmented into at leastthree interconnected parts. In addition, a bi-directional seal design isused in conjunction with a sliding control stem.

2. Description of Related Art

Gilmore Valve Company, the assignee of the present invention, has soldshear valves and other types of regulators for many years. Examples ofthese prior art devices are shown in U.S. Pat. Nos. 3,917,220 and4,493,335, both of which are included in the Information DisclosureStatement filed concurrently herewith. In order to adjust the set pointfor these prior art regulators, the operator was required to turn alarge handle at the top of the apparatus which would compress springs onthe inside of the apparatus. This was sometimes difficult at higher setpoints. Some prior art designs also had problems with dead bands.

Dead band is a generic term used to describe the envelope of performancewhen a regulator will not respond to pressure fluctuation. There areseveral types of dead band including forward adjustment dead band,reverse adjustment dead band, droop dead band and accumulation deadband. Generally, larger dead bands are less desirable because theydegrade the sensitivity of the regulator. Smaller dead bands can alsonegatively affect durability. Smaller dead bands can result in chatterand/or instability under uncertain flow conditions. There is a need fora design that optimizes the dead band characteristics of a regulator toachieve a balance between sensitivity, stability and durability.

It is known in the prior art to use dual seals in conjunction with eachother in order to multiply the sealing force being exerted by one of theseals. For example, in U.S. Pat. No. 3,455,566, a circular o-ring isdescribed as a unit force multiplying seal that exerts pressure on acontrolling seal that has a triangular cross section. Under compression,the shape of the circular o-ring is distorted and additional force istransferred to the second seal. However, this prior art design onlyworks when pressure is applied from a specific direction. There is aneed for an improved dual seal arrangement so that the second seal willfunction regardless of the direction of pressure that is being appliedto the other seal.

BRIEF SUMMARY OF THE INVENTION

Prior art regulators are often difficult to adjust accurately at higherpressures, because the adjustment knob must push against the full forceof a spring on the inside of the apparatus. In the present invention,the adjustment knob moves internal mechanisms including a small diametercontrol stem, not the spring.

Rotation of the adjustment knob of the present invention only requiresminimum force. The higher forces and torques of prior art regulatorstended to wear out the threads in the adjustment mechanism. The lowerforces in the present invention minimize this wear.

Strong individuals are sometimes known to turn adjustment knobs too hardand strip the threads or ruin prior art regulators. A common solution tothis problem in prior art devices is anti-rotation pins. The presentinvention does not have anti-rotation pins and is believed to have aunique solution to the problem of excess torque. If the adjustment knobon the present invention is turned beyond full open or full close, itmerely causes the internal mechanisms including the control stem torotate, rather than strip threads or break.

The body of the present regulator includes at least three interconnectedsegments. This segmented body design reduces inventory carrying costs.When an order is received, final machining of port size and type can bedone for each segment. These segments are then assembled with elongatebolts to define the interconnected body. Thus the number of componentsrequired for inventory can be held to a minimum.

The present regulator has improved dead band response. If the setpressure of a regulator is adjusted upward from the forward adjustmentset point, until the regulator just starts to supply, then the forwardadjustment dead band (sensitivity) is the amount that the pressureincreases until it stabilizes. Some prior art regulators including theGilmore 44577 and other competitive regulators had a forward adjustmentdead band in excess of 200 psi. If the set pressure of a regulator isadjusted downward from the reverse adjustment set point, until theregulator just starts to vent, then the reverse adjustment dead band(sensitivity) is the amount that the pressure decreases until itstabilizes. Some prior art regulators including the Gilmore 44577 andother competitive regulators had a reverse adjustment set point inexcess of 200 psi. The present invention has less than a 50 psi forwardand reverse adjustment dead band.

Droop dead band is the number of psi that the down stream pressure fallsbelow the forward adjustment set point before the regulator starts tosupply fluid. Some prior art regulators, including the Gilmore 44577 andother competitive regulators, had droop dead bands in the neighborhoodof 20% of the set pressure. The present invention droop dead band isapproximately 125 psi, even up to a 9000 psi set pressure.

Accumulation dead band is the number of psi that the downstream pressureincreases above the forward adjustment set point before the regulatorstarts to vent fluid. Some prior art regulators, including the Gilmore44577 and other competitive regulators, sometimes had accumulation deadband in the neighborhood of 20% of the set pressure. The presentinvention accumulation dead band is nearer to 6%.

The seal assembly in the present invention is a bi-directional pressureenergized design that allows for lower friction between the control stemand the seals. The seal assembly includes both an o-ring and a sealring. The o-ring energizes and increases the force against the seal ringwhich seals against the control stem.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevation view of the regulator with the vent portfacing outward.

FIG. 2 is a bottom view of the regulator of FIG. 1.

FIG. 3 is a section view of the regulator along line 3—3 of FIG. 2. FIG.3 shows the three segments of the body interconnected by elongate bolts.

FIG. 4 is a sectional illustration of the regulator of FIG. 1 taken outof hand so all of the ports can be seen in one drawing. The regulator inFIG. 4 is in the no flow or neutral position. In production, thefunction, supply and vent ports are actually aligned as shown in FIG. 1.

FIG. 5 is a sectional illustration of the regulator of FIG. 4, exceptthe regulator is in the open position with fluid flowing from the supplyport through the regulator to the function port as indicated by the flowarrows. Again, the ports are taken out of hand so all ports can be seenin one drawing.

FIG. 6 is a sectional illustration of the regulator of FIG. 4 except theregulator is shown in the vent position with fluid flowing from thefunction port through the regulator and out the vent port as indicatedby the flow arrows. Again, the ports are taken out of hand so all portscan be seen in one drawing.

FIG. 7 is an enlargement of the supply seal assembly in the neutralposition as shown along the line 7 of FIG. 4.

FIG. 8 is an enlargement of the vent seal assembly in the vent positionas shown along the line 8 of FIG. 6.

FIG. 9 is an enlarged section view of one-half of the bi-directionalsupply seal assembly and control stem without any force being exerted onthe o-ring or the seal ring. This is sometimes referred to as theun-energized position.

FIG. 10 is an enlarged section view of a portion of the bi-directionalsupply seal assembly in the energized position. Pressure is beingexerted on the o-ring and the seal ring as indicated by the arrows.

FIG. 11 is an enlarged section view of a portion of the bi-directionalsupply seal assembly in the energized position. Pressure from theopposite direction is being exerted against the o-ring and the seal ringas indicated by the arrows.

FIG. 12 is an enlarged perspective view of the control stem and otherinternal components of the regulator of FIG. 4.

FIG. 13 is an exploded perspective view of all components of theregulator of FIG. 4.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a side elevation view of the regulator with segmented bodygenerally identified by the numeral 20. A adjustment knob 22 is securedto the adjustment stem 24 by jam nut 26, not shown in this figure. Theadjustment knob 22 is rotated clockwise or counter-clockwise to adjustthe set point of the regulator 20. Retainer cap 28 is attached to springhousing 30 by a plurality of bolts 32, 34, 36 and 38. (Bolts 36 and 38are not shown in this figure.) A first mounting bracket 40 is connectedto a second mounting bracket 42, better seen in FIG. 2. The mountingbrackets are secured by bolts 44 and 46.

The segmented body 50 includes a function segment 52, a supply segment56 and a vent segment 60. These interconnected segments, 52, 56 and 60are sometimes referred to as pucks, because of their resemblance tohockey pucks. The function segment 52 includes the function port 54.(The port 54 is also sometimes referred to as the regulated port, thecylinder port or simply the outlet). The supply segment 56 includes thesupply port 58. (The port 58 is sometimes referred to as the inlet.) Thevent segment 60 includes the vent port 62. (The port 62 is sometimesreferred to as the vent.) Typically, each port is threaded to facilitatewith piping, hose or some other type of conduit. The supply port 58 isconnected to and is in fluid communication with a pressurized fluidsupply source, not shown. The function port 54 is connected to and is influid communication with a downstream apparatus, not shown. The ventport 62 is in fluid communication with atmosphere. The spring housing 30threadibly engages the body 50 at the function segment 52, as betterseen in other figures.

FIG. 2 is a bottom view of the regulator 20 of FIG. 1. A plurality ofbolts, 62, 64, 66 and 68 secure the vent segment 60 to the supplysegment 66 and the function segment 52 as better seen in the nextfigure. A nametag 70 is secured to the bottom of the vent segment 60 bydrive screws 72 and 74. First mounting bracket 40 is connected to secondmounting bracket 42 by bolts 44 and 46.

FIG. 3 is a section view of the regulator 20 along the line 3—3 of FIG.2. This figure better illustrates how the segmented body 50 isassembled. Elongate bolts 62 and 68 pass through apertures in the ventsegment 60, the supply segment 56 and engage threaded holes in thefunction segment 52. Though not shown in this figure, elongate bolts 64and 66 likewise connect segments 52, 56 and 60. This design allows eachsegment, 52, 56 and 60 to be machined and put in inventory withoutporting. When an order is received each segment is drilled and taped forthe specific port size and type required by the customer. This allowsthe manufacturer to reduce the amount of inventory required for thisproduct because each of the respective segments 52, 56 and 60 can beported on an as needed basis.

The function port 54, the supply port 58 and the vent port 62 can beordered in various sizes including ¼ inch, ⅜ inch, ½ inch, {fraction(9/16)} inch and perhaps others. Ports 54, 58 and 62 can also be tappedwith various thread designs as required by the customer including MediumPressure (MP), National Pipe Thread (NPT), Joint Industry Council (JIC)and Society of Automotive Engineers (SAE).

An axial passageway 100 is formed in the center of each of therespective body segments 52, 56 and 60. The shape of the axialpassageway 100 varies along its length. The lower control stem 82 ispositioned in the axial passageway 100. The lower control stem 82 movesup and down in the axial passageway in order to regulate the downstreampressure in the function port 54. (Port 54 is sometimes also referred toas a cylinder port).

In order to achieve a seal between the vent segment 60 and the supplysegment 56, a channel 106 is formed on the interior face 57 of the ventsegment 60 surrounding the axial passageway 100. An o-ring 108 ispositioned in the channel 106 to achieve a seal between the vent segment60 and the supply segment 56. Those skilled in the art will recognizethat the o-ring 108 could also be positioned in the face 59 of thesupply segment 56.

A vent seal assembly generally identified by the numeral 111 achieves aseal between the body 50 and the lower control stem 82 at the junctionof segments 56 and 60. A channel 110 is formed in the interior face 57of the vent segment 60 to receive the vent seal assembly 111 whichincludes an o-ring 112 and a seal ring 114. The vent seal assembly 111,which is enlarged in FIG. 8, is bisectional as will be described ingreater detail below. Those skilled in the art will recognize that thevent seal assembly could also be positioned in the face 59 of the supplysegment 56.

In order to achieve a seal between the function segment 52 and thesupply segment 56, a channel 116 is formed on the interior face 53 ofthe function segment 52. An o-ring 118 is positioned in the channel 116to achieve a seal between the function segment 52 and the supply segment56. Those skilled in the art will recognize that the o-ring 110 couldalso be placed in the face 61 of supply segment 56.

A supply seal assembly generally identified by the numeral 119 achievesa seal between the body 50 and the lower control stem 82 at the junctionof segments 56 and 52. A channel 120 is formed on the interior face 53of the function segment 52. The channel 120 receives the supply sealassembly 119 which includes an o-ring 122 and a seal ring 124. Thesupply seal assembly 119 is bi-directional like the vent seal assembly111.

The regulator 20 has three positions: the neutral or no flow position ofFIG. 4, the open position of FIG. 5 and the vent position of FIG. 6.Like most regulators, the primary purpose of the present invention is toregulate or otherwise control the pressure at the function port 54 to adownstream apparatus. The set point (also called set pressure) can beadjusted up or down over a range of approximately 500 to 10,000 psi. Inorder to lower the regulated pressure or set point, the adjustment knobis turned counter clockwise. To raise the set point the adjustment knob22 is turned clockwise.

When the regulator 20 moves from the neutral position of FIG. 4 to theopen position of FIG. 5, the lower control stem 82 moves downward movingthe upper flow slots 81 adjacent the supply seal assembly 119. Supplypressure then moves from the supply port 58 through the upper flow slots81 and past the supply seal assembly 119, through the axial passageway100 and out the function port 54. When the regulator 20 moves from theneutral position of FIG. 4 to the vent position of FIG. 6, the lowercontrol stem 82 moves upward positioning the lower flow slots 83adjacent the vent seal assembly 111. Excess pressure then moves from thefunction port 54 through other internal passageways and out the ventport 62 to atmosphere. The manner in which the lower control stem 82moves up and down will be described below.

FIG. 4 is a sectional illustration of the regulator of FIG. 1 taken outof hand so all the ports can be seen in one drawing. In production, theports are actually aligned as shown in FIG. 1. In FIG. 4, the regulator20 is shown in the no flow or neutral position. In this position, theouter circumference 79 of the lower control stem 82 is in sealingengagement with the supply seal assembly 119 which in conjunction withthe intermediate seal assembly 212 contains the supply pressure in thesupply port 58. The outer circumference 79 of the lower control stem 82is also in sealing engagement with the vent seal assembly 111 preventingany fluid from the function port 54 escaping to the vent port 62. Thusthere is no fluid flow through the regulator 20 in FIG. 4.

As previously discussed, the adjustment knob 22, not shown in thisfigure, is rotated clockwise or counter-clockwise to adjust the setpoint which controls the regulated pressure in the function port 54.When the adjustment knob 22 is turned, this rotation is imparted to theadjustment stem 24. One end of the adjustment stem 24 is secured to theadjustment knob 22 with a jam nut 26. A clevis 150 is formed on theopposite end of the adjustment stem 24. The clevis 150 slips over theadjusting sleeve pin 152. An outwardly projecting circumferential flange154 is formed in the mid-section of the adjustment stem 24. The flange154 is captured between the retainer cap 42 and the spring retainer 70,allowing just enough room for the stem 24 to rotate. Therefore, the knob24 and adjustment stem 24 can rotate but are fixed axially to the springhousing 30.

The adjusting sleeve 156 has a hollow bore 159 through the longitudinalaxis and an outwardly extending circumferential flange 157 on one end.The stem retainer 151 threadibly engages the spring guide 166 andcaptures the outwardly extending radial circumferential flange 157 ofthe adjusting sleeve 156 against the bottom of the spring guide 166counter bore, allowing just enough clearance for the adjusting sleeve156 to rotate. Therefore, the adjustment sleeve 156 is allowed torotate, but is fixed axially with respect to the spring guide 166.

The adjusting sleeve 156 has a transverse bore 151 on the end oppositethe flange 157. The adjusting sleeve pin 152 passes through thetransverse bore 151 in the adjusting sleeve 156 and the clevis 150 inthe adjustment stem 24. Therefore, when the adjusting knob 22 isrotated, the adjustment stem 24, rotates as well as the adjusting sleevepin 152 and the adjusting sleeve 156. The clevis 150 allows theadjusting sleeve 156 to move axially with respect to the adjustment stem24 and knob 22. One end of the sleeve 156 has threads 158 below wherethe transverse bore 151 is positioned. The threads 158 engage threads 25on the upper control stem 160. Axial pin 164 passes through a transversehole 165 in the spring guide 166 and a transverse slot 162 in the uppercontrol stem 160.

The pin 164 in the slot 162 allows the upper control stem 160 to moveaxially, but not rotationally with respect to the spring guide 166. Theresult is that as the adjusting sleeve 156 is rotated relative to thespring guide 166, the upper control stem 160 moves axially with respectto the spring guide 166. The lower control stem 82 is pinned to theupper control stem 160 by the pin 164. The two stems 82 and 160 moveaxially together.

Thus, rotation of the knob 22 causes the upper control stem 160 and thelower control stem 82 to move axially with respect to the spring guide166, while allowing the spring guide 166 to move axially with respect tothe knob 22, spring housing 30 and valve body 50. Thus, rotating theknob 22 counter-clockwise brings the set point to o psi and rotating theknob 22 clockwise brings the regulator 20 to its maximum set point.

The spring guide 166 includes an outwardly extending radial flange 168on one end which captures the belleville spring 169 against the springretainer 70. The belleville spring 169 has a longitudinal centralopening 171 sized and arranged to receive the spring guide 166. Thespring guide pin 167 passes through a transverse bore 165 in the springguide 166 and slips back and forth in the slot 162 of the upper controlstem 160. This feature allows adjustment of the lower control stem 82independent of the spring 169. Rotation of the knob 22 does not increaseor decrease the force being applied against the spring 169 by the springguide 166. The force that is applied to the spring 169 is appliedthrough the sensor piston 102 that is in contact with the flange 108 ofthe spring guide 166. Pressure from the function port 54 is appliedagainst the sensor piston 102 which is then transferred via the flange168 on the spring guide 166 to the spring 169.

The sensor piston 102 threadibly engages the retaining nut 180. Thesensor piston 102 includes an external o-ring groove 172, which receiveso-ring 174 and a back up ring. The o-ring 174 and back-up ring achieve adynamic seal between the function segment of body 50 and the sensorpiston 102. The sensor piston also has an axial through hole sized toreceive the lower control stem 82. The retaining nut 180 captures theo-ring 182 and another back-up ring 184 to achieve a dynamic sealbetween the sensor piston 102 and the lower control stem 82. The lowercontrol stem 82 includes a plurality of flow slits 81 that permit fluidflow from the supply port 58 to the function port 54 when the flow slits81 are proximate the supply seal assembly 119. A second set of flowslits 83 are formed in the lower control stem 82 which permit fluid toflow from the function port 54 to the vent port 62 when the flow slits83 are proximate the vent seal assembly 111.

FIG. 5 is a sectional illustration of the regulator of FIG. 1 taken outof hand so all of the ports can be seen in one drawing. In FIG. 5 is asectional illustration of the regulator 20 in the open position allowingfluid to flow from the supply port 58 to the function port 54 whichraises downstream pressure to the predetermined set point. In order tomove from the no-flow or neutral position of FIG. 4 to the open positionof FIG. 5, the lower control stem 82 must move downwards causing theupper flow slots 81 to move proximate the supply seal assembly 119 thusallowing fluid to flow from the supply port 58 through the flow slits 81to the function port 54. The present regulator is rated to operate atpressures of up to 10,000 psi. The maximum flow rate is approximately 10gpm. However, more typical flow rates will be in the range of 3-5 gpmwhen the regulator 20 is in the open position of FIG. 5.

The lower control stem 82 is moved downward as shown in FIG. 5 byrotating the control knob 22 clockwise. This adjusts the set point inthe function port 54. When the control knob 22 is rotated clockwise, theadjustment stem 24 to the adjustment stem 24 is rotated clockwise whichrotation is then imparted through the adjusting sleeve pin 152 to theadjusting sleeve 156. The reverse threads 158 on the adjusting sleeve156 and the threads 161 on the upper control stem 160 cause the uppercontrol stem 160 to move downward in response to the clockwise rotationof the control knob 22. The upper control stem 160 is able to movedownward because of the slot 162 which allows axial movement vis-a-visthe spring guide pin 167. The lower control stem 82 is connected to theupper control stem 160 by the control stem pin 164. The upper controlstem 160 and the lower control stem 82 move axially as a unit. As amatter of manufacturing choice, the upper control stem 160 and the lowercontrol stem 82 could be fabricated as a single part.

As the lower control stem 82 moves downward, the outer circumference 79of the lower control stem 52 moves away from the supply seal assembly119, thus allowing fluid to pass through the flow slits 81 in the lowercontrol stem 82, through the bore 10, to the function port 54, as shownby the flow arrows in the drawing. After the pressure in the functionport 54 increases to set point or set pressure, axial force from thefluid in passageway 100 is exerted upon the retaining nut 180 and thesensor piston 120. As the sensor piston moves upward, it transfers theaxial force to the flange 168 of the spring guide 166, thus compressingthe spring 169. As the spring guide 166 moves upward, this axialmovement is transferred to the stem retainer 151 and the adjustingsleeve 156. The threads 158 in the adjusting sleeve 158 engage thethreads 161 on the upper control stem 160, thus imparting upward axialmovement to the lower control stem 82, thus moving the lower controlstem 82 upward, when the adjusting sleeve 156 moves upward. As the lowercontrol stem 82 moves upward the flow slits 81 move upward and the outercircumference 79 of the lower control stem 82 again engages the supplyseal assembly 119, thus blocking further flow from the supply port 58into the function port 54.

If, for some reason, the regulated pressure drops (i.e., the pressure inthe function port 54), the spring 169 will relax. The sensor piston 102will move downward until the flow slits 81 are proximate to the supplyseal assembly 119. Fluid will flow from the supply port 26 until thepressure increases to the set point which will be enough to move theouter circumference 79 of the lower control stem 82 back into engagementwith the supply seal assembly 119.

The supply seal assembly 119 is held in place in the function segment 52by the upper end 206 of the sleeve 200. This relationship is better seenin the enlargement, FIG. 7. The sleeve 200 has a longitudinal bore 202which is sized and arranged to allow the lower control stem 82 to movefreely relative to the sleeve 200. A plurality of transverse bores 204allow fluid communication between the longitudal bore 202 of the sleeve200 and the axial bore 100 of the regulator 20.

The other end 208 of the sleeve 200 holds an intermediate seal assembly212 in place. The intermediate seal assembly 212 is not bi-directional.This intermediate seal assembly 212 is positioned in a channel 214 inthe supply segment 56 of the body 50. The channel 214 holds theintermediate seal assembly 212 which consists of an o-ring 216 and aback-up ring 218. The intermediate seal assembly 212 forms a sealbetween the lower control stem 82 and the supply segment 56 of the body50 to prevent supply pressure from escaping to vent. Supply pressure istherefore isolated in the supply port 58 by the intermediate sealassembly 212, the supply seal assembly 119 and the o-ring 118.

When there is an excess pressure in the function port 54, the lowercontrol stem 82 moves axially upward, thus allowing the fluid to movefrom the function port 54 to the vent port 62, as better seen in thenext figure.

FIG. 6 is a sectional illustration of the regulator 20 of FIG. 1 takenout of hand so all of the ports can been seen in one drawing. In FIG. 6of the regulator 20 in the vent position. On occasion, downstreampressure exceeds the set point or controlled pressure and it isnecessary to vent this excess pressure to atmosphere. When this occurs,the excess pressure in the function port 54 drives the sensor piston 102upward. As the sensor piston 102 moves upward, so does the lower controlstem 82. When the lower flow slots 83 move proximate the vent sealassembly 111, fluid flows from the function port 54 through variousinternal passageways and out the vent port 62. Fluid flows though thelower flow slots 83 past the vent seal assembly 111.

The function port 54 is in fluid communication with the axial passageway100 and another passageway 230. Another passageway 232 is formed in thefunction segment of the body 50. Another vertical passageway 234 isformed in the supply segment 56 of the body 50 and is aligned and influid communication with the passageway 232 in the function section 52of the body 50. In order to form a seal at the junction of thepassageways 232 and 234, a channel 236 is formed in the face 53 of thefunction section 52. An o-ring 238 is positioned in the channel 236 toform a seal between the function segment 52, the supply segment 56 andthe passageways 232 and 234. Another passageway 240 is formed in thesupply section 56 of the body 50. Passageway 240 is in fluidcommunication with passageway 234 and axial passageway 100. Passageway240 is sealed to atmosphere by a lee-type plug 242.

When venting, fluid moves as indicated by the flow arrows from thefunction port 54, through the axial passageway 100, the passageway 230,the passageway 232, the passageway 234, the passageway 240 and back tothe axial passageway 100. The fluid then moves through the lower flowslots 83 in the lower control stem 82 thus passing the vent sealassembly 111 back into the axial passageway 100 and thereafter exitingthe regulator 20 at vent port 62.

As the venting process occurs, the amount of pressure on the sensorpiston 102 diminishes. When this overcomes a predetermined set point,the force in the spring 58 overcomes the forces in the sensor pistonchamber 103, thus driving the spring guide 166 back to its lowerposition of FIG. 4. When the spring guide 166 moves axially downward, itcauses the upper control stem 160 and the lower control stem 82 to movedownward, which causes the lower flow slots 83 to move downward and thusthe outside circumference 79 of the lower control stem 82 re-engageswith the vent seal assembly 111 thus stopping fluid flow to vent.

The lower control stem 82 has maximum up and down axial positions oftravel caused by rotation of the knob 22. When the knob 22 is turnedcounter clockwise, the lower control stem 82 moves downward (i.e. awayfrom the knob 22) to a zero psi set point (because of the reversethreads). The maximum downward position of travel of control stem 82 isreached when the spring guide pin contacts the upper extremity 173 ofslot 162 in upper control stem 160. If the knob 22 is further rotatedcounter clockwise when the lower control stem 82 is in its maximumdownward position, various internal components will rotate rather thanstrip or otherwise damage the regulator 20. The following “spinning”components freely rotate when the knob 22 is rotated infinitely in acounter clockwise direction: the adjustment stem 24, the adjustingsleeve pin 152, the adjusting sleeve 156, the upper control stem 160,the spring guide pin 167, the spring guide 166, the stem retainer 151,the control stem pin 165 and the lower control stem 82.

When the knob 22 is turned clockwise, the lower control stem 82 movesupward (i.e. towards the knob 22) because of the reverse threads, to amaximum psi set point. The maximum upward position of travel of lowercontrol stem 82 is reached when the spring guide pin contacts the lowerextremity 171 of slot 162 in the upper control stem 160. If the knob 22is further rotated clockwise when the lower control stem 82 is in itsmaximum upward position, various internal components will freely rotaterather than strip or otherwise damage the regulator. The same “spinning”components listed above freely rotate when the knob 22 is rotatedinfinitely in a clockwise direction.

The movement of the control stem from the maximum up position to themaximum down position is approximately 0.025 inches. However, inoperation, the typical amount of movement from the open position in FIG.5 to the vent position of FIG. 6 is from approximately 0.010 inch to0.020 inch. Other distances may be suitable depending on the size of theregulator and other manufacturing considerations.

The ability of the “spinning” components to freely rotate when the knob22 is infinitely rotated clockwise or counter clockwise is due to theoverall design of the valve and the bi-directional seal assemblies 119and 111. The ability of the “spinning” components to freely rotate whenthe knob 22 is infinitely rotated prevents damage and stripping to theregulator 20.

FIG. 7 is an enlargement of a portion of the regulator 20 along the line7 from FIG. 4. FIG. 7 shows the regulator 20 in the neutral or no-flowposition. In the no flow position, the outer circumference 79 of thecontrol stem 82 seals against the seal ring 124 of the supply sealassembly 119. The upper flow slots 81 on the lower control stem 82 arepositioned above the supply seal assembly 119 in the no flow positionthus precluding any fluid flow from the supply port 58 past the supplyseal assembly 119. Fluid in the supply port 58 is contained because ofthe supply seal assembly 119, the intermediate seal assembly 212 and theo-ring 118.

FIG. 8 is an enlargement of the portion of the regulator 20 along theline 8 of FIG. 6. FIG. 8 shows the regulation 20 in the vent positionwith the flow slits 83 adjacent the vent seal assembly 111. Whenventing, fluid moves from the passageway 240 through the axialpassageway 100 through the lower flow slots 83 past the vent sealassembly 111 and back into the axial passageway 100 in the vent segment60 of the body 50 to vent port 62.

FIGS. 9, 10 and 11 are cross-sectional enlargements of a portion of thebi-directional supply seal assembly 119. The bi-directional vent sealassembly 111 functions in a similar fashion to the supply seal assembly119 and is configured in a similar, but opposite arrangement as seen inFIG. 8. FIG. 9 shows the seal in the unenergized position. FIG. 10 showsthe seal energized by downstream pressure indicated by the arrows. FIG.11 shows the seal energized in the opposite direction by upstreampressure indicated by the arrows. In FIG. 10 and FIG. 11 a seal isachieved between the seal ring 124 and the exterior circumference 79 ofthe control stem 82 as a result of forces that are applied against theo-ring 122 which urges the seal ring 124 into sealing engagement withthe lower control stem 82.

The adjustment assembly moves the control stem (i.e., the upper controlstem 160 and the lower control stem 82) axially from the neutralposition to the open position to regulate pressure in the function port54, to the downstream apparatus and to move the control stem axiallyfrom the neutral position to the vent position when excess pressureoccurs in the function port 54 to vent the excess pressure toatmosphere. For purposes of claim interpretation, the term adjustmentassembly includes the adjustment knob 22, the adjustment stem 24, thespring housing 30, the spring 169, the spring guide 166, the springguide pin 167, the sensor piston 102, the adjusting sleeve 156, theadjusting sleeve pin, and the stem retainer 151.

FIG. 9 is an enlarged section view of one-half of the supply sealassembly 119. A channel 120 also referred to as an o-ring supportstructure, is defined by four walls. The channel 120 includes a firstwall 250 a second wall 252, a third wall 254 and a fourth wall 256.Walls 250, 252 and 254 are formed in the function segment 52 of the body50. The fourth wall 256 is formed by he upper portion 206 of sleeve 200.The walls 250 and 254 are parallel. The walls 252 and 256 are alsoparallel. The wall 254 extends less than half the length of the wall250, thus creating an opening 255 from the channel 120 to the axial bore100. A flat seal ring 124 is positioned in the opening 255 between thewall 254 and the wall 256 of sleeve 200. The o-ring 122 is positioned inthe channel 120. The lower control stem 82 is shown in reducedperspective to save space; the drawing is not proportioned to the sizeof the o-ring 122 in the actual embodiment.

Applicants have found that a ⅜ inch outside diameter×¼ inch insidediameter×{fraction (1/16)} inch cross-section BUNA N90 duro National C67compound o-ring is suitable for the o-ring 122. Other o-rings withsimilar properties from other manufacturers such as Parker may also besuitable. Applicants have found that a 0.260 inch outside diameter×0.184inch inside diameter×0.034 inch thick seal ring manufactured from PEEK(polyethetherketone) is suitable for the seal ring 124. Other materialswith similar rigidity and strength properties to PEEK may also besuitable.

Those skilled in the art will understand that the seal ring 124 iscircular in shape and fully surrounds and contacts the outsidecircumference 79 of the lower control stem 82 when the seal assembly isenergized. They will likewise recognize that the o-ring 122 is circularin shape and therefore it completely encircles but does not contact thelower control stem 82.

FIG. 10 is an enlarged section view of a portion of the supply sealassembly 119 showing the seal being energized by upstream fluid pressurefrom supply port 58. The supply seal assembly 119 is energized byupstream fluid pressure from supply port 58 when the regulator is theneutral position of FIG. 4. When the seal is energized as shown in FIG.10 it prevents the fluid pressure in the supply port 58 from passing tothe function port 54. To energize the supply seal assembly, upstreamfluid pressure from the supply port 58 moves through the axialpassageway 100 through the bores 204 in the sleeve 200 and through thebore 202 of sleeve 200. The force of the hydraulic fluid, as indicatedby the arrows, compresses and distorts the o-ring 122 causing it toprotrude into the opening 255 and contact the outside circumference 125of seal ring 124. When it protrudes into the opening 255, it exertsforce on the seal ring 124 as indicated by the arrow A. This forceachieves a seal between the outer circumference 79 of the lower controlstem 82 and the inner circumference 123 of seal ring 124 thus preventingsupply pressure to move from the supply port 58 to the function port 54.

FIG. 11 shows the bi-directional supply seal assembly 119 energized inthe opposite direction of FIG. 10. FIG. 11 shows the supply sealassembly 119 energized by downstream forces as it would be when theregulator 20 is venting as shown in FIG. 6. In the vent position, excesspressure from the function port 54 moves down the axial passageway 100and enters the channel- 120 compressing and distorting the o-ring asshown by the arrows. The o-ring 122 then exerts pressure against theoutside circumference 125 of seal ring 124 in the direction of the arrowB. A seal is therefore achieved between the seal ring 124 and the lowercontrol stem 82 preventing over-pressure from moving from the functionport 54 to the supply port 858.

The vent seal assembly 111 is also bi-directional. When the regulator 20is in the no-flow position of FIG. 4, upstream fluid pressure from thesupply port 58 energizes the vent seal assembly 111 achieving a sealbetween the seal ring 114 and the lower control stem 82, preventingsupply pressure from escaping to vent. Specifically, the upstream fluidpressure enters the channel 110 compressing and distorting the o-ring112 which exerts pressure against the outside circumference 113 of theseal ring 114. The inside circumference 115 of the seal ring 114 thenachieves a seal with the outside circumference 79 of the lower controlstem 82.

When the regulator 20 moves to the vent position of FIG. 6, downstreamfluid pressure from the function port 54 energizes the vent sealassembly 111 from the opposite direction, achieving a seal between theseal ring 114 and the lower control stem 79 preventing excess pressurefrom entering the supply port 58. Specifically, the downstream fluidpressure enters the channel 111 compressing the o-ring 112 from theopposite direction. The o-ring 112 exerts pressure against the outsidecircumference 113 of the seal ring 114. The inside circumference 115 ofthe seal ring is then urged into sealing contact with the outsidecircumference 81 of the lower control stem 81.

FIG. 12 is an exploded perspective view of some of the internalcomponents of the regulator 20. The lower control stem 82 is connectedto the upper control stem 160 by the control stem pin 164 which passesthrough opposing bores 163 and 165 in the upper control seem 160.Threads 161 on the upper control stem 160 threadably engage the internalbore 158 of the adjusting sleeve 156. The clevis 150 of adjustment stem24 engages the adjusting sleeve pin 152. Pin 152 passes throughtransverse bore 151 in adjusting sleeve 156. When the adjustment stem 24is rotated by the adjustment knob 22, it causes the adjusting sleeve 156to rotate. When the adjusting sleeve 156 rotates it causes the uppercontrol stem 160 and the lower control stem 182 to move axially relativeto the regulator 20 because of the threaded engagement at 158. In thismanner, the set point of the regulator can be adjusted up or down.Rotation of the adjustment 22 counter-clockwise brings the set point ofthe regulator to zero psi and rotation clockwise brings the regulator 20to its maximum set point.

FIG. 13 is an exploded view of the regulator with segmented body 20. Theregulator 20 use fewer parts than the prior Gilmore design No. 44820,also described in U.S. patent application Ser. No. 09/640,401 filed onAug. 16, 2000 and is therefore more economical to produce. It is alsoeasier to assemble. This design also eliminates many of the smallprecision parts required in prior art designs. This design uses leeplugs instead of JIC plugs.

The adjustment knob 22 is attached to the adjustment stem 24 by a jamnut 26. The retainer cap 28 is connected to the spring housing 30 bybolts 32, 34, 36 and 38. The adjustment stem 24 is captured between theretainer cap 28 and the spring housing 30 so that it does not moveaxially. The adjustment stem 24 can be rotated by movement of theadjustment knob 22. The belleville spring 169 is captured between theflange 168 on the spring guide 166 and the bottom end of the springretainer 70. Bolts 62, 64, 66 and 68 pass through holes in the ventsegment 60 and the supply segment 58 and threadably engage holes in thefunction segment 52. Four bolts 62, 64, 66 and 68 secure theinterconnected segments 52, 56 and 58 thus forming the body 50. Othersecuring means may also be used to interconnect the segments 52, 56 and58 to form the body 50. The seals and other internal components havebeen previously described.

What is claimed is:
 1. A regulator connected to a pressurized fluidsupply and a downstream apparatus to regulate the pressure to thedownstream apparatus and to vent excess pressure to atmosphere, theregulator comprising: a body having three interconnected segmentsincluding a vent segment, a supply segment and a function segment; thevent segment defining a vent port connected to atmosphere, the supplysegment defining a supply port connected to the pressurized fluid supplyand the function segment defining a function port connected to thedownstream apparatus; an axial bore in the body sized and arranged toreceive an elongate control stem movable from a neutral position to anopen position and a vent position; a supply seal assembly positioned inthe body and encircling the control stem, to seal with the control stemand body to selectively allow the flow of fluid from the supply port tothe function port as the control stem moves axially from the neutralposition to the open postilion; a vent seal assembly positioned in thebody and encircling the control stem to seal with the control stem andthe body to selectively allow the flow of fluid from the function portto the vent port as the control stem moves axially from the neutralposition to the vent position; and an adjustment assembly to move thecontrol stem axially from the neutral position to the open position toregulate pressure in the function port to the downstream apparatus andto move the control stem axially from the neutral position to the ventposition when excess pressure occurs in the function port to vent theexcess pressure to atmosphere.
 2. The apparatus of claim 1 wherein theadjustment assembly comprises: a spring housing connected to the body;an adjustment stem having a knob on one end and a clevis on the otherend with the knob on an outside of the spring housing, the adjustmentstem and clevis rotating when the knob is rotated; a spring having alongitudinal center opening; an elongate tubular spring guide having acircumferential flange on one end, the spring carried by the tubularspring guide and being captured between the circumferential flange and aspring retainer, the tubular spring guide having a hollow longitudinalcentral bore and a transverse aperture; an elongate adjusting sleevehaving an axial central bore, the adjusting sleeve having a radialflange on one end and a transverse hole in the other end, the clevis ofthe adjustment stem being inserted in the axial central bore and theadjusting sleeve positioned in the hollow-longitudinal central bore ofthe spring guide on the end opposite the circumferential flange; anadjusting sleeve pin sized and arranged to fit in the transverse bore inthe adjusting sleeve and to engage an opening in the clevis so rotationof the knob and adjustment stem causes like rotation of the adjustingsleeve; a stem retainer engaging the hollow central bore of the springguide trapping the adjusting sleeve in the spring guide and causing theadjusting sleeve and stem retainer to move axially with the springguide; the elongate control stem having a transverse slot, the controlstem connected with reverse threads to the axial bore of the adjustingsleeve so rotation of the knob, adjustment stem and adjusting sleevecauses axial movement of the control stem; a spring guide pin sized andarranged to fit in the transverse aperture of the spring guide and topass through the transverse slot in the control stem; and a sensorpiston mounted in the body and exposed to pressurized fluid in thefunction port, the sensor piston abutting the spring guide so force fromthe pressurized fluid is transferred through the sensor piston andspring guide to the spring causing axial movement of the spring guide,stem retainer, adjusting sleeve and control stem to achieve regulationof the pressure in the function port.
 3. A regulator rated foroperational pressures of up to 10,000 psi connected to a pressurizedfluid supply and a downstream apparatus to regulate the pressure to thedownstream apparatus and to vent excess pressure to atmosphere, theregulator comprising: a body having three interconnected segmentsincluding a vent segment, a supply segment and a function segment; thevent segment defining a vent connected to atmosphere, the supply segmentdefining an inlet connected to the pressurized fluid supply and thefunction segment defining an outlet connected to the downstreamapparatus; an axial bore in the body sized and arranged to receive anelongate control stem movable from a neutral position to an openposition and a vent position; a supply seal assembly positioned in thebody and encircling the control stem, to seal with the control stem andbody to selectively allow the flow of fluid from the supply port to thefunction port as the control stem moves axially from the neutralposition to the open position; a vent seal assembly positioned in thebody and encircling the control stem to seal with the control stem andthe body to selectively allow the flow of fluid from the outlet to thevent as the control stem moves axially from the neutral position to thevent position; an adjustment assembly to move the control stem axiallyfrom the neutral position to the open position to regulate pressure inthe outlet to the downstream apparatus and to move the control stemaxially from the neutral position to the vent position when an excesspressure occurs in the outlet to vent the excess pressure to atmosphere;and the regulator having a forward and reverse adjustment dead band ofless than 50 psi, a droop dead band of approximately 125 psi and anaccumulation dead band of approximately 6% of set pressure.
 4. Theapparatus of claim 3 wherein the adjustment assembly comprises: a springhousing connected to the body; an adjustment stem having a knob on oneend and a clevis on the other end with the knob on an outside of thespring housing, the adjustment stem and clevis rotating when the knob isrotated; a spring having a longitudinal center opening; an elongatetubular spring guide having a circumferential flange on one end, thespring carried by the tubular spring guide and being captured betweenthe circumferential flange and a spring retainer, the tubular springguide having a hollow longitudinal central bore and a transverseaperture; an elongate adjusting sleeve having an axial central bore, theadjusting sleeve having a radial flange on one end and a transverse borein the other end, the clevis of the adjustment stem being inserted inthe axial central bore and the adjusting sleeve positioned in the hollowlongitudinal central bore of the spring guide on the end opposite thecircumferential flange; an adjusting sleeve pin sized and arranged tofit in the transverse bore in the adjusting sleeve and to engage anopening in the clevis so rotation of the knob and adjustment stem causeslike rotation of the adjusting sleeve; a stem retainer engaging thehollow central bore of the spring guide trapping the adjusting sleeve inthe spring guide and causing the adjusting sleeve and stem retainer tomove axially with the spring guide; an elongate control stem having atransverse slot, the control stem connected with reverse threads to theaxial bore of the adjusting sleeve so rotation of the knob, adjustmentstem and adjusting sleeve causes axial movement of the control stem; aspring guide pin sized and arranged to fit in the transverse aperture ofthe spring guide and to pass through the transverse slot in the controlstem; and a sensor piston mounted in the body and exposed to pressurizedfluid in the outlet, the sensor piston abutting the spring guide sopressure from the pressurized fluid is transferred through the sensorpiston and spring guide to the spring causing axial movement of thespring guide, stem retainer, adjusting sleeve and control stem toachieve regulation of the pressure in the outlet.
 5. A regulatorconnected to a pressurized fluid supply and a downstream apparatus toregulate the pressure to the downstream apparatus and to vent excesspressure to atmosphere, the regulator comprising: a body defining a ventport connected to atmosphere, a supply port connected to the pressurizedfluid supply and a function port connected to a downstream apparatus; anelongate control stem having a plurality of upper flow slots and aplurality of lower flow slots, the control stem moving axially in anaxial bore in the body; an adjustment knob positioned outside the bodyat the top of the regulator, the knob operatively connected to thecontrol stem to adjust the set pressure of the regulator; a supply sealassembly positioned in the body and encircling the control stem toselectively seal the body to the control stem; a vent seal assemblypositioned in the body and encircling the control stem to selectivelyseal the body to the control stem; and a sensor piston and springoperatively connected to the control stem to move the control stern andupper flow slots axially towards the supply seal assembly when pressurein the function port falls below set pressure so the upper flow slotsare proximate the supply seal assembly allowing fluid to flow from thesupply port to the function port, and when excess pressure occurs in thefunction port the control stem and lower flow slots are moved axiallytowards the vent seal assembly so the lower slots are proximate the ventseal assembly allowing fluid to flow from the function port to vent. 6.A regulator connected to a pressurized fluid supply and a downstreamapparatus to regulate the pressure to the downstream apparatus and tovent excess pressure to atmosphere, the regulator comprising: a bodydefining a vent port connected to atmosphere, a supply port connected tothe pressurized fluid supply and a function port connected to adownstream apparatus; an elongate control stem having a plurality ofupper flow slots and a plurality of lower flow slots, the control stemmoving axially in an axial bore in the body; a supply seal assemblypositioned in the body and encircling the control stem to selectivelyseal the body to the control stem; a vent seal assembly positioned inthe body and encircling the control stem to selectively seal the body tothe control stem; and a sensor piston and spring operatively connectedto the control stem to move the control stem axially from a neutralposition to a open position and alternatively to a vent position and anadjustment knob positioned outside the body, the knob operativelyconnected to the control stem to adjust a set pressure of the regulatorby axial movement of the upper flow slots and lower flow slots relativeto the supply seal assembly and the vent seal assembly.
 7. A regulatorconnected to a pressurized fluid supply and a downstream apparatus toregulate the pressure to the downstream apparatus and to vent excesspressure to atmosphere, the regulator comprising: a body defining a ventport connected to atmosphere, a supply port connected to the pressurizedfluid supply and a function port connected to a downstream apparatus; anelongate control stem having a plurality of upper flow slots and aplurality of lower flow slots, the control stem moving axially in anaxial bore in the body; a supply seal assembly positioned in the bodyand encircling the control stem to selectively seal the body to thecontrol stem; a vent seal assembly positioned in the body and encirclingthe control stem to selectively seal the body to the control stem; andan adjustment knob positioned outside the body of the regulator, theknob operatively connected to the control stem to adjust the setpressure of the regulator and the knob operatively connected to spinningcomponents so they can freely rotate without damage to the regulatorwhen the knob is infinitely rotated clockwise or counter clockwise.